Electrical contact

ABSTRACT

An electrical contact ( 100 ) for connecting an electronic package with a circuit substrate comprise a first part ( 1 ) and a second part ( 2 ). The first part ( 1 ) comprises a body portion ( 11 ) and a first spring arm ( 14 ) extending upwardly from the body portion ( 11 ), the first spring arm ( 14 ) defines a first contacting portion ( 141 ) at top end thereof. The second part ( 2 ) comprises a retention portion ( 21 ), a second spring arm ( 23 ) extending upwardly from the retention portion ( 21 ) and a solder portion ( 22 ) extending downwardly from the retention portion ( 21 ), the second spring arm ( 21 ) defines a second contacting portion ( 231 ) at top end thereof and the body portion ( 11 ) is fastened on the retention portion ( 21 ).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electrical contact, and moreparticularly to an electrical contact for electrically connecting apackage and a circuit substrate, and having two separated part assembledtogether which can provide two contacting points for the package.

2. Description of the Prior Art

Electrical connectors for removably mounting an LGA package on a PCB areknown as LGA sockets. An LGA socket typically comprises a substantiallyflat dielectric housing which is positioned between the LGA package andthe PCB. The housing defines an array of passageways with electricalcontacts received therein in correspondence with the array of pads ofthe LGA package. Each contact has a pair of oppositely extending freeends spaced apart with a predetermined distance in an original position.The two free ends extend beyond the housing for respectively engagingwith corresponding contacting pads on a bottom surface of the LGApackage and on a top surface of the PCB thereby establishing anelectrical connection between the LGA package and the PCB.

Various electrical contacts for LGA sockets are disclosed in the priorart, such as U.S. Pat. Nos. 5,653,598 issued to Dimitry on Aug. 5, 1997and 6,905,377 issued to Keith on Jun. 14, 2005. Typically, a contact foran LGA socket comprises a single contacting portion at an upper endthereof and a single soldering portion at a bottom end thereof. Thesingle contacting portion extends upwardly beyond an upper face of thesocket to contact with a corresponding contacting pad of an LGA package.The single soldering portion extends downwardly beyond a lower face ofthe socket to contact with a corresponding solder pad of a PCB.Therefore, an electrical connection is established between the singlecontacting portion of the LGA package and a corresponding soldering padof the PCB via a single contacting portion.

However, as the pads of the LGA package are increasing and the socket isreduced in size because of quick development of science, there islimited space for arranging the array of increasing contacts. Contactsfor an LGA socket are usually designed in a trend of miniaturization;such will increase impedance of transmitting signal. Furthermore, thepads of the PCB must also be increased as the increasing pads of the LGApackage and such increases the cost of the PCB manufacture. Thus, animproved contact for an LGA socket is required to overcome thedisadvantages of the conventional contact.

In view of the above, a new electrical contact that overcomes theabove-mentioned disadvantages is desired.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide anelectrical contact having two separated part assembled together and eachhaving a contacting portion connecting with the package.

To fulfill the above-mentioned object, an electrical contact comprises afirst part and a second part. The first part comprises a body portionand a first spring arm extending upwardly from the body portion, thefirst spring arm defines a first contacting portion at top end thereof.The second part comprises a retention portion, a second spring armextending upwardly from the retention portion and a solder portionextending downwardly from the retention portion, the second spring armdefines a second contacting portion at top end thereof and the bodyportion is fastened on the retention portion.

Other objects, advantages and novel features of the invention willbecome more apparent from the following detailed description when takenin conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of an electrical contact in accordance withthe first embodiment of the present invention;

FIG. 2 is an assembled view of the electrical contact in FIG. 1;

FIG. 3 is a side view of the electrical contact, showing the electricalcontact connected with a CPU and a PCB;

FIG. 4 is an exploded view of an electrical contact in accordance withthe second embodiment of the present invention;

FIG. 5 is an assembled view of the electrical contact in FIG. 4; and

FIG. 6 is a side view of the electrical contact in FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

Reference will now be made to the drawings to describe the presentinvention in detail.

Referring to FIG. 1 and FIG. 3, which depict the first embodiment of thepresent invention. The electrical contact 100 is used for electricallyconnecting an electronic package, such as a land grid array (LGA)central processing unit (CPU) 3, with a circuit substrate, such as aprinted circuit board (PCB) 4. The electrical contact 100 comprises afirst part 1 and a second part 2 separated with each other.

The first part 1 comprises a flat body portion 11, a first spring arm 14extending obliquely from the upper end of the body portion 11, a firstextending portion 114 extending upwardly from the upper end of the bodyportion 11 in a vertical direction and a pair of block portions 12, 13extending downwardly from the lower end of the body portion 11. Theblock portions 12, 13 are separated with each other at the lower end.The first spring arm 14 defines a first contacting portion 141 at topend thereof for electrically connecting with the CPU.

The second part 2 comprises a flat retention portion 21, a holdingportion 212 extending outwardly from the middle of the retention portion21, a second spring arm 23 extending obliquely from the upper end of theretention portion 21, a second extending portion 211 extending upwardlyfrom the upper end of the retention portion 21 in a vertical directionand a solder portion 22 extending downwardly from the lower end of theretention portion 21. The solder portion 22 is configured with a flatshape and extending in a horizontal direction. The second spring arm 23has a second contacting portion 231 at top end thereof for electricallyconnecting with the CPU. Please referring to FIG. 3, the holding portion212 is configured with a reversaled S shape and comprises a pressportion 2121 for pressing on the body portion 11, thus the body portion11 of the first part 1 is sandwiched by the pressing portion 2121 andthe retention portion 21, then the first part 1 is fastened on thesecond part 2 securely.

Referring to FIGS. 2-3, which shows an assembled view of the electricalcontact 100, the body portion 11 of the first part 1 is contact with theretention portion 21 of the second part and is sandwiched by thepressing portion 2121 and the retention portion 21. The pair of blockportions 12, 13 are located on the two sides of the holding portion 21,the lower end of the block portions 12,13 are on top of the solderportion 22 and the solder portion 22 is connected to the pad 41 of thePCB 4 through a solder ball 5. The first extending portion 114 and thesecond extending portion 211 contacts with each other and have the samesize. The first spring arm 14 is on top of the second spring arm 23 andthe first contacting portion 141 is in the same height with the secondcontacting portion 231 in the vertical direction and are connected withthe same pad 31 of the CPU 3.

Referring to FIG. 4, which depicts a second embodiment of the presentinvention. In this embodiment, the first part 1′ of the electricalcontact 200′ comprises a pair of shoulder portions 112′ and a pair ofprojections 111′ extending laterally from the body portion 11′. Theprojections 111′ is below the shoulder portion 112′ and forms a restrictspace 113′ together with the corresponding shoulder portions 112′. Thesecond part 2′ comprises a pair of fasten portions 214′ extendingoutwardly and downwardly from the retention portion 21′ and a holdingportion 213′ extends outwardly from the retention portion 21′.

Referring to FIGS. 5-6, showing the assembled view of the electricalcontact 200′, the body portion 11′ of the first part 1′ is contact withthe retention portion 21′ of the second part 2′ and the lower end of thebody portion 11′ is supported by the holding portion 213′. The lockingportions 12′,13′ are located on opposite sides of the holding portion213′, the fasten portions 214′ are received in the restrict spaces 113′and engaged with the shoulder portions 112′ and the projections 111′,thus the first part 1′ is fastened on the second part 2′ securely.

In the above detailed description, the electrical contact 100, 200′comprises a first part 1, 1′ with a first contacting portion 141 and asecond part 2, 2′ with a second contacting portion 231. The first part1, 1′ is assembled on the second part 2, 2′. Thus the electrical contact100, 200′ can provide at least two contacting portions 141, 231connecting with the CPU with fewer space.

It is to be understood, however, that even though numerouscharacteristics and advantages of the present invention have been setforth in the foregoing description, together with details of thestructure and function of the invention, the disclosure is illustrativeonly, and changes may be made in detail, especially in matters of shape,size, and arrangement of parts within the principles of the invention tothe full extent indicated by the broad general meaning of the terms inwhich the appended claims are expressed.

1. An electrical contact is used for electrically connecting anelectronic package, such as a land grid array (LGA), central processingunit (CPU), with a circuit substrate, comprising: a first partcomprising a flat body portion and a first spring arm extendingobliquely and forwardly from the body portion, the first spring armhaving a first contacting portion at free end thereof; and a pair ofblock portions separately extending downwardly from the lower end of thebody portion thereof for electrically connecting with the CPU; and asecond part and the first part being separated from each other; and thesecond part abutting on the first part, the second part comprising aflat retention portion extending in a vertical direction, a secondspring arm extending obliquely and forwardly from the retention portionand a solder portion extending downwardly from the retention portion andextending continuously in a horizontal direction as a flat portion formounting on the CPU, the second spring arm having a second contactingportion at free end thereof and the body portion being fastened on theretention portion; the second part comprises a holding portionprotruding rearwardly from the retention portion for holding the bodyportion of the first part onto the retention portion of the second partin a pressing manner.
 2. The electrical contact as claimed in claim 1,wherein the first spring arm is on top of the second spring arm, andwherein the first contacting portion and the second contacting portionare located in a horizontal plane.
 3. The electrical contact as claimedin claim 1, wherein, the body portion of the second part is used tosupport the body portion of the first part.
 4. The electrical contact asclaimed in claim 3, wherein the holding portion comprises a pressportion, the body portion of the first part is sandwiched by the pressportion and the retention portion of the second part.
 5. The electricalcontact as claimed in claim 3, wherein the first part comprises a pairof block portions extending downwardly from the body portion and locatedat opposite sides of the holding portion, the lower end of the blockportions are in the upper of the solder portion.
 6. The electricalcontact as claimed in claim 3, wherein the body portion comprises a pairof shoulder portions and a pair of projections below the shoulderportions.
 7. The electrical contact as claimed in claim 6, wherein thesecond part comprises a pair of fasten portions extending outwardly anddownwardly from the retention portion, and the fasten portions arelocated with the shoulder portions and the projections of the firstpart.
 8. The electrical contact as claimed in claim 6, wherein the firstpart and the second part each comprises an extending portion extendingupwardly from the body portion and the retention portion.
 9. Anelectrical contact is used for electrically connecting an electronicpackage, such as a land grid array (LGA), central processing unit (CPU),with a circuit substrate, comprising: a first part comprising a flatbody portion and a first spring arm extending obliquely and forwardlyfrom the body portion, the first spring arm having a first contactingportion at free end thereof; and a pair of block portions separatelyextending downwardly from the lower end of the body portion thereof forelectrically connecting with the CPU; and a second part and the firstpart being separated from each other; and the second part abutting onthe first part, the second part comprising a flat retention portionextending in a vertical direction, a second spring arm extendingobliquely and forwardly from the retention portion and a solder portionextending downwardly from the retention portion and extendingcontinuously in a horizontal direction as a flat portion for mounting onthe CPU, the second spring arm having a second contacting portion atfree end thereof and the body portion being fastened on the retentionportion; the first spring arm is in the upper of the second spring armand the first contacting portion is in the same height with the secondcontacting portion; the second part comprises a holding portionprotruding rearwardly from the retention portion for holding the bodyportion of the first part onto the retention portion of the second partin a pressing manner.
 10. The electrical contact as claimed in claim 9,wherein, the body portion of the second part is used to support the bodyportion of the first part.
 11. The electrical contact as claimed inclaim 10, wherein the holding portion comprises a press portion, thebody portion of the first part is sandwiched by the press portion andthe retention portion of the second part.
 12. The electrical contact asclaimed in claim 10, wherein the first part comprises a pair of blockportions extending downwardly from the body portion and located atopposite sides of the holding portion, the lower end of the blockportions are on top of the solder portion.
 13. The electrical contact asclaimed in claim 10, wherein the body portion comprises a pair ofshoulder portions and a pair of projections below the shoulder portions.14. The electrical contact as claimed in claim 13, wherein the secondpart comprises a pair of fasten portions extending outwardly anddownwardly from the retention portion for engaging with the shoulderportions and the projections of the first part.
 15. An electricalcontact set is used for electrically connecting an electronic package,such as a land grid array (LGA), central processing unit (CPU), with acircuit substrate, comprising: a first part comprising a firstupstanding main body portion and a first spring arm extending upwardlyand obliquely from the body portion, the first spring arm having a firstcontacting portion at free end thereof; and a second part and the firstpart being separated from each other; and the second part abutting onthe first part, the second part comprising a second upstanding main bodyportion extending in a vertical direction, a second spring arm extendingobliquely and forwardly from the second main body portion and a solderportion extending downwardly from the second main body portion andextending continuously in a horizontal direction as a flat portion formounting on the CPU, the second spring arm having a second contactingportion at free end thereof and the first body portion being fastened onthe second body portion; and only one solder pad unitarily formed on abottom portion of only one of said first main body and said second mainbody; wherein the first main body portion and the second main bodyportion are intimately face to face attached to each other; at least oneof said first part and said second part defines a retention portion forretaining the intimately fastened first and second parts in aninsulative housing of an electrical connector.
 16. The electricalcontact set as claimed in claim 15, wherein an extension angle of saidspring arm and that of the second spring arm are different from eachother in a side view.
 17. The electrical contact set as claimed in claim15, wherein said first spring arm and said second spring arm areessentially spaced from each other while an upper contact region of thefirst spring arm and that of the second spring arm are coplanar on asame horizontal plane.
 18. The electrical contact set as claimed inclaim 17, wherein a distance between said first spring arm and saidsecond spring arm is various under condition that a maximum value occursbetween the upper contact regions of said first spring arm and saidsecond spring arm while a minimum value occurs between roots of saidfirst sprint arm and said second spring arm.
 19. The electrical contactset as claimed in claim 15, wherein the second spring arm is essentiallylocated under the first spring arm, and the solder pad is formed on thesecond part.
 20. The electrical contact set as claimed in claim 19,wherein the extension angle of the first spring arm is steeper than thatof the second spring arm.